For 2010 it's the thing.
Those claims may be easy to dismiss or laugh off, but if Microsoft is trying to get some open source street cred then everyone else is too. And there are now thousands of programs where elements of open and closed source are mixed.
For years makers of closed source programs have sought to at least connect with open source standards, through plug-ins or APIs. More recently we have seen elements of major programs, like Adobe's PDF format, go open source. This is often followed by a flood of open source alternatives to the main package.
It goes the other way too. The whole idea of Eclipse is to give vendors an open source shared store from which proprietary programs can be built. BSD-type licenses explicitly allow closed source to be built with open, and many open source companies have debated closing some "secret source" in order to maintain cash flow.
When there's an open source "community" version and a paid "enterprise" version of the same software, what is the difference between writing a check for enterprise support and just buying a closed source license?
As open source increasingly becomes an enterprise mandate, you can expect such questions to gain new relevancy. How open do you have to be? How closed must you be?
These questions have been a feature of leading-edge open source commentary all year, as illustrated by our own Matt Asay. Once a staunch GPL advocate, he no longer reflexively condemns Microsoft's open source efforts. Baby indeed needs a new pair of shoes.
Who knows, maybe O'Reilly will do a book on this, with some strange beastie on the cover. What would an OSINO look like? (Open Source In Name Only.)
What thought leaders talk about one year often becomes common currency the next. Many claims of openness are going to be challenged next year, and my only prediction is that the identity of the attacker may sometimes surprise you.
I may have to update my famous open source incline, maybe adding a third dimension. Or even a fourth.